1. Field of the Invention
This invention relates to the flatting of glossy surfaces. More particularly, it relates to a method for flatting polyurethane films and coatings.
2. Description of the Prior Art
Floor coverings having polyurethane films as wear layers have been relatively recent developments in the art. Films of these materials are characterized by a combination of toughness, scratch resistance, traffic durability, and high gloss that exceeds that of the conventional films of the prior art, such as the vinyls and the alkyds. While advantageous in many applications, the high gloss associated with polyurethane coatings and films is sometimes objectionable. For example, when such coatings or films are employed over dark colored substrates, minute scratches in the glossy surface appear, such contrasting as starkly white against the dark background. In attempts to subdue the glossiness of these surfaces, fillers such as calcium carbonate and diatomaceous earth have been added to the formulations. Generally, such fillers result in the sacrifice of the physical properties of the wear layer, such as traffic abrasion and tensile strength. The fillers are also responsible for inhibiting the polyurethane-forming reaction, lengthening processing times considerably. As a result, the competitive advantages of the polyurethanes over the prior art wear layer floor coverings are substantially diminished or totally destroyed.